Tag Archives: Environment

Climate-Driven Extinction Made Mammals’ Teeth Less Weird

WIRED

Fossils show how species diversity—and dental diversity—suddenly collapsed 30 million years ago, suggesting a link between climate, diet, and survival.

DORIEN DE VRIES always asks for permission before flying across the world to touch someone else’s teeth. Some of the owners are anxious. Their teeth are fragile—irreplaceable. But de Vries, a paleontologist, sets their minds at ease. She knows how to be extra careful. “It’s exactly the same as dentists’,” she says of the gooey paste she uses to capture the tooth topography. “It sets really quickly and you can peel it off.” She casts the molds and then 3D-scans the replica teeth into digital immortality.

Well, maybe not exactly like a dentist. The teeth De Vries is working with are up to 56 million years old—they once belonged to the mammals of the late Eocene, Oligocene, and Miocene Epochs and are now preserved in museum and university collections.

Read the full story in WIRED.

The Artificial Leaf: Copying Nature to Fight Climate Change

ACS ChemMatters Magazine

An ancient chemical process enabled Earth to become a lush place teeming with life. Now researchers are replicating this process in an attempt to slow global warming.

Every plant, animal, and person owes their life to one sequence of chemical reactions: photosynthesis. The process, which converts water and carbon dioxide into food using sunlight, first evolved in cyanobacteria more than 2 billion years ago.

That’s right. Plants weren’t the first organisms to develop photosynthesis, though they are better known for it. Cyanobacteria are the ones that originally filled the atmosphere with photosynthesis’s gaseous by-product, oxygen (O2), which set the stage for more diverse life on Earth.

As beneficiaries of photosynthesis, humans depend on plants in a sort of carbon seesaw. Plants take in CO2 and release O2. They store that carbon as sugar. Hanging vines, grass, and trees all grow by pulling carbon atoms out of the air. We do the reverse, taking in O2 and releasing CO2. Finally, everything we eat completes the handoff: Human eats plant (or the animal who already did), human exhales, plant stores carbon, and the cycle continues.

This seesaw is part of the much broader carbon cycle that has affected the radiation balance of our planet. Cutting down huge swaths of forests and the burning of carbon-based fossil fuels causes the levels of CO2, a major greenhouse gas, to rise. And plants on Earth along with other natural parts of the carbon cycle can’t restore the balance on their own.

But what if we could copy what plants do to grab some of that excess CO2 to make fuels sustainably, instead of relying so heavily on fossilized carbon?

Read the full story in the October 2021 issue of ChemMatters

The Long-Lost Tale of an 18th-Century Tsunami, as Told by Trees

WIRED

Local evidence of the cataclysm has literally washed away over the years. But Oregon’s Douglas firs may have recorded clues deep in their tree rings.

ONE NIGHT IN late January 1700, two tectonic plates running along the Pacific Northwest coast released the tension they had accumulated during a centuries-long tête-à-tête. In a tectonic roar, the Juan de Fuca plate slipped past the North American plate, and a roughly 9.0-magnitude earthquake rattled the entire region. The coastline dropped and tsunamis washed over the entire Northwest coast.

Read the full story in WIRED

The Race to Put Silk in Nearly Everything

WIRED

The fiber has been considered a “miracle material” for anything from body parts to food. Has the revolution finally arrived?

ALI ALWATTARI STILL remembers the day he met the goats. It was mid-May, 19 years ago, in Quebec. The sun was lighting up the old maple sugar farm—and small huts where the goats were living. Alwattari, a materials scientist, had spent his career tinkering with chemistry equipment for Procter & Gamble, developing fibers used in Pampers and Swiffers. But the startup Nexia Biotechnologies was aiming to use an entirely different kind of polymer producer—and it was gazing back at him with its rectangular pupils.

Read the full story in WIRED

How Many People Die When Polluters Exceed Their Limits?

WIRED

A new report tallies the death toll from excess emissions by looking at air pollution and spikes in local ozone levels.

MEASURING AIR QUALITY is inherently a measure of excess—any amount of toxic nitrogen oxides, ground-level ozone, and fine particulate matter is probably bad for human health. But when it comes to federal regulations, the notion of excess gets a bit wonky. When a refinery or plant outstrips the limits set by the local public health authorities to cap pollution, those fumes are considered “excess emissions,” or, more wonkily still, “exceedances.”

Emissions limits are arbitrary, of course. Less pollution is always better in a country where more than 20 people die every hour from poor air quality, and where that burden skews toward communities of color. But parsing the human cost of these overflows is helpful for weighing—or possibly tightening—those arbitrary limits. So Nikolaos Zirogiannis, an environmental economist at Indiana University, decided to quantify the health toll in one state: How many people die each year as a result of that extra pollution?

Read the full story in WIRED

Hungry, Hungry Microbes in Tree Bark Gobble Up Methane

WIRED

Bad news: Trees emit methane, a greenhouse gas. Good news: Some are home to bacteria that can’t get enough of it.

MANY OF TODAY’S geoscientists are carbon voyeurs. Knowing that human disregard for the carbon cycle has screwed the climate, they have kept a close eye on carbon’s hottest variants—carbon dioxide (CO 2) and methane. Both gasses trap heat on the planet through the greenhouse effect, and over a span of 100 years methane is 28 times more potent than CO2. Rigorously accounting for greenhouse gas flow is step one of building models that predict the future climate.

Some line items in the methane budget, such as pipeline leaks and cow farts, are well understood. But others are hazier. “There’s lots of gaps and uncertainties, particularly in wetlands, and inland waters,” says Luke Jeffrey, a biogeochemistry postdoc at Southern Cross University in Australia. By one 2020 tally from the Global Carbon Project, wetlands emit about 20 to 31 percent of Earth’s annual methane release—more than the amount from fossil fuel production.

But in the past decade, researchers have zeroed in on a perhaps counterintuitive source of greenhouse gas emissions: trees. Freshwater wetland trees, in particular. Trees bathing in wet or flooded soil absorb methane and then leak it through their bark. In a 2017 study, ecologist Sunitha Pangala, then at the Open University in the United Kingdom, found that trees in the Amazon were responsible for 200 times more methane than trees in other wetland forests, accounting for 44 to 65 percent of the region’s total emissions.

Does this mean trees are bad for the planet? Of course not. Trees suck carbon dioxide out of the atmosphere. And in a study published April 9 in Nature Communications, Jeffrey and his team report how trees can also be methane sinks, sheltering microbes that convert it to the less damaging CO2.

Read the full story in WIRED

Ocean Acidification Could Make Tiny Fish Lose Their Hearing

WIRED

Their inner ears turn wonky when they grow up in carbon-rich water, which could keep juveniles from finding their way to the reefs. That could mean trouble.

AN IMMOBILIZED FISH lay between Craig Radford’s fingers. The several-week-old Australasian snapper, no longer than a pinkie nail, rested flat on a slab of modeling clay, held down by small staples—“as someone would strap you down on an ambulance bed to hold you there,” says Radford. He stuck tiny electrodes on the fish’s head, then submerged it in a tank and switched on an underwater speaker. It was time to test its hearing.

“If you actually put your head underwater and take the time to listen, it’s amazing what you’ll hear,” Radford says. “From whales to fish to crustaceans—sound plays an important role in many, many different species’ life strategies.”

But Radford’s experiment wasn’t due to curiosity about what the world sounds like to fish. He was worried about how well they could hear it.

Read the full story in WIRED

Are Forever Chemicals Harming Ocean Life?

THE REVELATOR

Here’s what we know (and don’t know) about how dangerous PFAS chemicals travel ocean currents and harm wildlife — and what that could mean for humans.

In seabird after seabird, Anna Robuck found something concerning: per- and polyfluoroalkyl substances, or PFAS, lurking around vital organs.

“Brain, liver, kidney, lung, blood, heart,” Robuck says, rattling off a few hiding spots before pausing to recall the rest. Robuck, a Ph.D. candidate in chemical oceanography at the University of Rhode Island, quickly settles on a simpler response: She found the chemicals everywhere she looked.

PFAS — a group of synthetic chemicals — are often called “forever chemicals” due to their quasi-unbreakable molecular bonds and knack for accumulating in living organisms. That foreverness is less of a design flaw than a design feature: The stubborn, versatile molecules help weatherproof clothing; smother flames in firefighting foam; and withstand heat and grime on nonstick pans.

Through consumption and disposal, the chemicals seep into ecosystems and bodies, where they have been linked to cancers, pregnancy complications, and reproductive and immune dysfunction. Recent attention has focused on the prevalence of PFAS in drinking water.

“Over the past 10-15 years we’ve really developed this super negative picture of what PFAS do to humans,” Robuck says. “But we’ve barely scratched the surface of that in wildlife.”

Read the full story in The Revelator

Cicadas Are Delightful Weirdos You Should Learn To Love

SMITHSONIAN

As Brood IX takes flight for the first time in 17 years, cicada lovers have their ears open.

Around this time of year, Marianne Alleyne hosts dozens of houseguests in her basement. Far from using camping equipment or cots, they sleep upside-down, clinging to a curtain. The entomologist at the University of Illinois Urbana-Champaign has collected cicadas, those bizarre and misunderstood cyclical insects, for four years.

“In Illinois, we have 20 species, and hardly anything is known about them,” Alleyne says. “We know very little about what they’re doing underground.”

Cicadas have a longstanding reputation as loud, swarming pests that keep obnoxiously particular schedules. In the United States, they got a bad rap from the beginning, as early colonists misidentified these clouds of emerging cicadas as locusts. “They were thought of as a biblical plague,” says John Cooley, an assistant professor in residence at the University of Connecticut. That impression has been a lasting one: a group of cicadas is still referred to as a plague or a cloud. “The question I get the most is ‘How do I kill them?’” Cooley says.

Read the full story in Smithsonian